Collection assistance secures reciprocal recovery of tax claims, interest, and penalties, subject to final determination and public policy. Collection assistance allows the Contracting States to cooperate in recovering taxes, interest, costs and civil penalties defined as a revenue claim, but only after the requesting State certifies that the claim is finally determined and that adequate taxpayer assets are unavailable domestically. Amounts collected are forwarded to the requesting authority, with possible reimbursement of collection costs by agreement, and assistance is limited by each State's collection practices and public policy. The article's application commences on a mutually agreed date between competent authorities.